1. Technical Field of the Invention
The present invention relates to the combined or associated administration of adapalene and of benzoyl peroxide for reducing the number of acne lesions. 6-[3-(1-Adamantyl)-4-methoxyphenyl]-2-naphthoic acid (referred to hereinbelow as adapalene) is a naphthoic acid derivative with retinoid and anti-inflammatory properties. This molecule was developed for the topical treatment of common acne and of dermatoses sensitive to retinoids.
2. Description of Background and/or Related and/or Prior Art
Adapalene is marketed under the trademark Differin® at a weight concentration of 0.1%, in the form of an “alcoholic lotion” solution, an aqueous gel and a cream. These compositions are useful for treating acne. FR 2,837,101 describes adapalene compositions at a weight concentration of 0.3%, for treating acne.
WO 03/0555 472 and corresponding US 2003/0170196 moreover describe stable pharmaceutical compositions comprising adapalene and benzoyl peroxide (BPO).
An article by Korkut and Piskin, J. Dermatology, 2005, 32: 169-173, reports the results of a study comparing a treatment combining application of adapalene in the evening and application of BPO in the morning, relative to an application of each of the active principles alone. The authors do not observe any superiority of the combined treatment over a period of 11 weeks of treatment.